JP No. 11(1999)-334431A discloses a seat sliding device having a seat sliding main body, a locking mechanism and a memorizing mechanism. The seat sliding main body is configured with a lower rail fixed at a vehicle floor and extending in a seat longitudinal direction and an upper rail fixed at a seat and slidably guided by the lower rail. The memorizing mechanism includes a memory slide, which is attached at the lower rail and can be switched between a slidable movement along the lower rail and a fixed condition thereto. The locking mechanism is attached at the upper rail and establishes a locked or unlocked condition between the upper rail and the lower rail. A cooperation of the locking mechanism and the memorizing mechanism enables a seat return from a seat position set after a seat walk-in movement to an occupant's seated position set before the seat walk-in movement.
However, in the aforementioned seat sliding device, each of the locking mechanism and the memorizing mechanism has been attached at an outer surface of the seat sliding main body. Therefore, an area for placing each mechanism at the seat sliding main body is constrained. Further, the number of components for the cooperation thereof may be increased, thereby causing a high manufacturing cost. Still further, the above-described structure may increase a lateral dimension of the seat sliding device, thereby narrowing a below space for an occupant to be seated at a rear seat.
Further, the lower rail is required to have an engaging hole for engaging the memory slide at the lower rail. This structure may deteriorate rigidity of the lower rail.
A need exists for providing an improved seat sliding device having a smaller lateral dimension, a fewer components and a memorizing mechanism with sufficient rigidity.